Hmm. Taking a look at the code, there's not really a provision for escaping in this manner. And unfortunately, this is parsed in various places throughout xymonlaunch (and passed onto the shell).

The only workaround that seems to work properly is substitution prior to xymoncmd's reading:

in xymonserver.cfg: NORRDDISKS='^(/dev|/tmp|/var)$FOO'

then run: env FOO='$' xymoncmd env | grep NORRD

You could either place FOO='$' in a shell wrapper launched from tasks.cfg, or stick it way up in /etc/sysconfig/xymonlaunch (if you're using the RPM).

I'm tempted to try a patch allowing '$$' to mean an unprocessed '$', but that might interfere with people who want a shell PID for some reason. Alternatively, adding '\' escaping globally in environment files might cause other sorts of problems for folks.

Alternatively-alternatively, NORRDDISKS='^(/dev|/tmp|/var)\Z' might work for you, since this *is* just straight PCRE...

-jc

On Wed, March 2, 2016 11:23 am, Matt Vander Werf wrote:

Hi J.C.,

It doesn't seem to be working with or without the escape backslash. It doesn't show up in the env output either way.

root@<host> ~]# grep NORRDDISK /etc/xymon/xymonserver.cfg NORRDDISKS="^/dev|^/var|^/tmp$" [root@<host> ~]# xymoncmd env | grep NORRD 2016-03-02 14:18:47.151545 xgetenv: Cannot find value for variable NORRDDISKS=^/dev|^/var|^/tmp

[root@<host> ~]# grep NORRDDISK /etc/xymon/xymonserver.cfg NORRDDISKS="^/dev|^/var|^/tmp\$" [root@<host> ~]# xymoncmd env | grep NORRD 2016-03-02 14:17:47.233910 xgetenv: Cannot find value for variable NORRDDISKS=^/dev|^/var|^/tmp

When I do it with them grouped together, it gives me the same result:

[root@<host> ~]# grep NORRDDISK /etc/xymon/xymonserver.cfg NORRDDISKS="^(/dev|/var|/tmp)$" [root@<host> ~]# xymoncmd env | grep NORRD 2016-03-02 14:20:35.984507 xgetenv: Cannot find value for variable NORRDDISKS=^(/dev|/var|/tmp)

Any ideas?

Thanks!!

-- Matt Vander Werf

On Wed, Mar 2, 2016 at 11:50 AM, J.C. Cleaver <cleaver at terabithia.org> wrote:

...

...

Hello,

Looking at past list e-mails, it is my understanding that the NORRDDISKS setting in xymonserver.cfg allows for PCRE regular expressions. Is this correct? Or does it only allow certain PCRE regular expressions, but not everything?

I ask because I'm experiencing an issue with my NORRDDISKS setting.

I'd like to ignore disks for graphing that have mount points "/tmp", but not ignore disks with mount points that have "tmp" in them, like "/tmpscratch".

I noticed that for other disk mount point names that if you just use "^/<name>" with no modifiers, then it only ignores disk mount points with only exactly "^/<name>" and not "^/<name><additional text>" or "^/<name>/<more name>" (at least from what I can tell).

For example when using:

NORRDDISKS="^/dev|^/tmp|^/var"

It ignores disks with mount points "/dev" and "/var", but also "/tmp" AND "/tmpscratch". But it doesn't look like it ignores "/var/tmp" (at least as far as I can tell).

I tried using "^/tmp$" and that didn't work either (still ignored both names).

Any idea what's going on here? Or how this can be done correctly? Is the "$" metacharacter not allowed in this setting?

If it's needed, I'm running the latest 4.3.26-1 Terabithia RPM on RHEL

On Wed, March 2, 2016 8:31 am, Matt Vander Werf wrote: 7.

...

Thanks for any help!!

-- Matt Vander Werf

Try checking the output of 'xymoncmd env | grep NORRD' ? If the '$' is not coming through, it might be getting read in as an attempt at a shell variable.

If so, can you try escaping it as \$ instead?

Alternatively: '^(/dev|/tmp|/var)$'

HTH, -jc

The 'env' would be unnecessary, however I just realized that you're running on EL7. systemd strikes again, unfortunately...

The shell wrapper shim is the easiest solution

Create a chmod 755 file /tmp/blah:

#!/bin/sh

NORRDDISKS='^(/dev|/tmp|/var)$' export NORRDDISKS

exec $*

Then edit your xymond_rrd CMD line from something like: CMD xymond_channel --channel=data xymond_rrd --rrddir=$XYMONVAR/rrd to CMD xymond_channel --channel=data /tmp/blah xymond_rrd --rrddir=$XYMONVAR/rrd

(same for 'status').

That *should* set it properly. You can remove it from the normal xymonserver.cfg file if you like.

This is definitely a complete hack, but I'm not sure what the best long-term fix is, like I said.

HTH,

-jc

On Wed, March 2, 2016 1:01 pm, Matt Vander Werf wrote:

Hi J.C.,

Adding the '\Z' instead of '$' doesn't seem to work either.

[root@<host> ~]# xymoncmd env | grep NORRD NORRDDISKS=^/dev|^/var|^/tmpZ

How would I do that shell wrapper launched from tasks.cfg?

I tried to stick it in /etc/sysconfig/xymonlaunch and it came back with an error message "Ignoring invalid environment assignment 'env FOO=$': /etc/sysconfig/xymonlaunch" and "xymoncmd[15102]: 2016-03-02 15:55:16.622168 xgetenv: Cannot find value for variable FOO".

Just putting in FOO='$' without the 'env' didn't work either.

Thanks for your help!!

-- Matt Vander Werf

On Wed, Mar 2, 2016 at 3:06 PM, J.C. Cleaver <cleaver at terabithia.org> wrote:

...

Hmm. Taking a look at the code, there's not really a provision for escaping in this manner. And unfortunately, this is parsed in various places throughout xymonlaunch (and passed onto the shell).

The only workaround that seems to work properly is substitution prior to xymoncmd's reading:

in xymonserver.cfg: NORRDDISKS='^(/dev|/tmp|/var)$FOO'

then run: env FOO='$' xymoncmd env | grep NORRD

You could either place FOO='$' in a shell wrapper launched from tasks.cfg, or stick it way up in /etc/sysconfig/xymonlaunch (if you're using the RPM).

I'm tempted to try a patch allowing '$$' to mean an unprocessed '$', but that might interfere with people who want a shell PID for some reason. Alternatively, adding '\' escaping globally in environment files might cause other sorts of problems for folks.

Alternatively-alternatively, NORRDDISKS='^(/dev|/tmp|/var)\Z' might work for you, since this *is* just straight PCRE...

-jc

On Wed, March 2, 2016 11:23 am, Matt Vander Werf wrote:

...

Hi J.C.,

It doesn't seem to be working with or without the escape backslash. It doesn't show up in the env output either way.

root@<host> ~]# grep NORRDDISK /etc/xymon/xymonserver.cfg NORRDDISKS="^/dev|^/var|^/tmp$" [root@<host> ~]# xymoncmd env | grep NORRD 2016-03-02 14:18:47.151545 xgetenv: Cannot find value for variable NORRDDISKS=^/dev|^/var|^/tmp

[root@<host> ~]# grep NORRDDISK /etc/xymon/xymonserver.cfg NORRDDISKS="^/dev|^/var|^/tmp\$" [root@<host> ~]# xymoncmd env | grep NORRD 2016-03-02 14:17:47.233910 xgetenv: Cannot find value for variable NORRDDISKS=^/dev|^/var|^/tmp

When I do it with them grouped together, it gives me the same result:

[root@<host> ~]# grep NORRDDISK /etc/xymon/xymonserver.cfg NORRDDISKS="^(/dev|/var|/tmp)$" [root@<host> ~]# xymoncmd env | grep NORRD 2016-03-02 14:20:35.984507 xgetenv: Cannot find value for variable NORRDDISKS=^(/dev|/var|/tmp)

Any ideas?

Thanks!!

-- Matt Vander Werf

On Wed, Mar 2, 2016 at 11:50 AM, J.C. Cleaver <cleaver at terabithia.org> wrote:

...

On Wed, March 2, 2016 8:31 am, Matt Vander Werf wrote:

...

Hello,

Looking at past list e-mails, it is my understanding that the NORRDDISKS setting in xymonserver.cfg allows for PCRE regular expressions. Is this correct? Or does it only allow certain PCRE regular expressions,

but

...

...

everything?

I ask because I'm experiencing an issue with my NORRDDISKS setting.

I'd like to ignore disks for graphing that have mount points "/tmp", but not ignore disks with mount points that have "tmp" in them, like "/tmpscratch".

I noticed that for other disk mount point names that if you just use "^/<name>" with no modifiers, then it only ignores disk mount points with only exactly "^/<name>" and not "^/<name><additional text>" or "^/<name>/<more name>" (at least from what I can tell).

For example when using:

NORRDDISKS="^/dev|^/tmp|^/var"

It ignores disks with mount points "/dev" and "/var", but also "/tmp" AND "/tmpscratch". But it doesn't look like it ignores "/var/tmp" (at least as far as I can tell).

I tried using "^/tmp$" and that didn't work either (still ignored both names).

Any idea what's going on here? Or how this can be done correctly? Is the "$" metacharacter not allowed in this setting?

If it's needed, I'm running the latest 4.3.26-1 Terabithia RPM on RHEL

not 7.

...

Thanks for any help!!

-- Matt Vander Werf

Try checking the output of 'xymoncmd env | grep NORRD' ? If the '$' is not coming through, it might be getting read in as an attempt at a shell variable.

If so, can you try escaping it as \$ instead?

Alternatively: '^(/dev|/tmp|/var)$'

HTH, -jc